I have a BB on BES for my company email, however I have 2 personal email accounts (imap and pop3) that I'd like to be able to read. I was using logicmail but find it very slow and tedious to work with. Is there a good 3rd party client for managing "additional" email accounts?

If you can't add them to your BB the old fashioned way, through BES/BIS, like any other email account, then it's because of your company's IT Policy. Circumventing that policy is usually a very bad thing, ie: grounds for immediate termination. I'm just sayin'....